TEKS 7.4B Review

TEKS 7.4B Review

7.4B calculate unit rates from rates in mathematical and real-world problems

Rates and Unit Rate

Rate: A rate is a special ratio (fraction) in which the two terms (x and y) are in different units. For example, if a 12-ounce can of corn costs 69¢, the rate is 69¢ for 12 ounces

Unit Rate: A type of ratio that compares an amount of one quantity to 1 unit of another quantity (Unit rates are expressed with a denominator of 1 unit.

Calculating Unit Rate

Calculating Unit Rate

Step 1: Identify your x and y values

x = time ; y = square feet painted

Step 2: Set up your ratio (a fraction in the form y/x)

55 square feet / .50 (half an hour)

Step 3: Calculate Unit Rate by dividing y by x (y is in the numerator, x is in the denominator)

55/.50 = 110/1 ; In one hour, Angela is able to paint 110 sq ft.

YOUR TURN!

Work through the following problems on calculating Unit Rate.

Multiple Choice

Driving at a constant speed for 5 hours, a traveler has covered 300 miles. What is the unit rate in miles/hour?

• 5/300 miles per hour

• 60 miles per hour

• 50 miles per hour

• 30 miles per hour

Multiple Choice

James just filled up his truck with gas. He paid $28.75 and got 11.5 gallons of gas. What is the Unit Rate? (What is the cost of 1 gallon of gas?)

• $2.50 per gallon

• $3.50 per gallon

• $4.00 per gallon

• $3.00 per gallon

Multiple Choice

If Analissa puts 55 seeds into 11 pots, how many seeds does she put in 1 pot?

• 4

• 5

• 6

• 7

Multiple Choice

Calculate the unit rate for each product. Which is the better deal?

• Cheerios

• Apple Jacks

• Both have the same unit rate.

Multiple Choice

At 0 seconds, Mrs. Taylor was 10 feet off the ground. At 5 seconds, she was 20 feet off the ground. What is her rate in feet per second?

• 5 feet per second

• 0 feet per second

• 2 feet per second

• 4 feet per second

Multiple Choice

I bought 10 tickets for $9.25 each to go the new Star Wars movie. If I had a $100 bill, do I have enough money to pay for all the tickets?

• Yes, and I have $7.50 left

• Are you kidding? There are no tickets left for that movie!

• Yes, and I have $6.50 left

• No! I need much more money than that!

Multiple Choice

Andy, Alfredo, and Karlo go to the movies and to play video games in the movie arcade. Altogether they spend $145.56. They find $20 on the floor and use that towards their bill. The rest they split it evenly. About how much money did each pay?

• $41.85

• $125.56

• $436.68

• $63.89

Multiple Choice

A store sees 120 customers in 8 hours. What is the unit rate (in customers per hour)?

• 16 customers per hour

• 12 customers per hour

• 20 customers per hour

• 15 customers per hour

Multiple Choice

At what rate did the rain fall?

• 2 cm per hour

• 1/2 cm per hour

• 4 cm per hour

• 1/4 cm per hour

Multiple Choice

Josh bought a pizza with eight slices of pizza for $12. What is the cost of a slice of pizza?

• $12

• $1.50

• $1.00

• $3.50